CN113795931A

CN113795931A - Light emitting diode and manufacturing method thereof

Info

Publication number: CN113795931A
Application number: CN202180003024.0A
Authority: CN
Inventors: 黄苡叡; 林宗民; 邓有财; 张中英
Original assignee: Quanzhou Sanan Semiconductor Technology Co Ltd
Current assignee: Quanzhou Sanan Semiconductor Technology Co Ltd
Priority date: 2021-06-02
Filing date: 2021-06-02
Publication date: 2021-12-14
Anticipated expiration: 2041-06-02
Also published as: KR20230145322A; US20230081600A1; CN113795931B; WO2022252137A1

Abstract

The invention discloses a light emitting diode and a manufacturing method thereof, wherein the manufacturing method comprises the following steps: providing an LED wafer, wherein the LED wafer comprises a substrate and a light-emitting epitaxial lamination layer positioned on the upper surface of the substrate, and the light-emitting epitaxial lamination layer comprises a first type semiconductor layer, an active layer and a second type semiconductor layer from one side of the substrate; secondly, defining a cutting channel on the upper surface of the LED wafer, wherein the cutting channel comprises a first cutting direction and a second cutting direction which are vertical to each other; providing a laser beam to focus in the substrate, forming X cutting lines on the same cross section in the substrate along a first direction, and forming Y cutting lines on the same cross section in the substrate along a second direction, wherein Y is greater than X and greater than 0, and Y is greater than or equal to 3; and fourthly, separating the LED wafer into a plurality of LED chips along the cutting channel.

Description

Light emitting diode and manufacturing method thereof

Technical Field

The invention relates to the technical field of semiconductors, in particular to a light-emitting diode and a manufacturing method thereof.

Background

A Light Emitting Diode (LED) is a semiconductor device that emits light by using energy released during carrier recombination, and particularly, a flip-chip LED chip thereof has been widely used due to advantages of low energy consumption, long service life, energy saving, environmental protection, and the like.

In the manufacturing process of the LED chip, a series of laser scratches are formed inside a sapphire substrate of an LED wafer in an industry by using a laser stealth cutting method, and then the LED wafer is cut by using a splitting method to form the LED chip. Most of the sapphire substrates used in the method are wafer with a large c-plane (0001), and as shown in fig. 1, in the laser cutting process of the LED wafer, the whole circular wafer needs to be divided into a plurality of rectangular single core particles. Two mutually perpendicular cutting directions perpendicular to the C-plane of the sapphire, generally corresponding to the sapphire crystal

And

due to the fact that

Face close to slip face

And slip plane

The surface is not vertical to the c surface and has a certain oblique angle, and the laser cut single finished core particle is

The actual direction of splitting of the face being along

The surface is subjected to lattice movement, so that actual cracks deviate from the middle of a cutting channel, when the width of the cutting channel is large, the crack position can be ensured not to extend to a chip light-emitting electrode area (electrode), but the yield is increased as much as possible in actual processing, so that the width of the cutting channel is smaller and smaller, and the chip light-emitting electrode area is scratched due to the fact that the cracks deviate from the middle of the cutting channel, and the problem of electric leakage is caused. As shown in FIG. 2, an included angle of 90+/-10 degrees is formed on the side of the LED chip after the LED wafer is split, so that the problems of large and small edges, irregular shape and the like are easily caused at the edge outside the periphery of the light-emitting epitaxial lamination. Fig. 3 is a photograph showing a real photograph in which the LED chips 100 shown in fig. 2 are arranged on a substrate, and it can be seen that the shapes of the back surfaces of the LED chips (back surfaces of the substrate) are irregular, and the light distribution is not uniform when the light emitted from the light emitting epitaxial stack is emitted outward from the substrate. Fig. 4 shows a light distribution graph of the LED chip shown in fig. 2, where the light pattern is asymmetric due to the edge distortion of the chip.

Disclosure of Invention

Accordingly, the present invention is directed to a light emitting diode and a method for fabricating the same that overcome at least one of the disadvantages of the prior art.

In some embodiments, the present invention provides a method for manufacturing a light emitting diode, comprising the steps of:

providing an LED wafer, wherein the LED wafer comprises a substrate and a light-emitting epitaxial lamination layer positioned on the upper surface of the substrate, and the light-emitting epitaxial lamination layer comprises a first type semiconductor layer, an active layer and a second type semiconductor layer from one side of the substrate;

secondly, defining a cutting channel on the surface of the LED wafer, wherein the cutting channel comprises a first cutting direction and a second cutting direction which are vertical to each other;

providing a laser beam to focus in the substrate, forming X cutting lines on the same cross section in the substrate along a first direction, and forming Y cutting lines on the same cross section in the substrate along a second direction, wherein Y is greater than X and greater than 0, and Y is greater than or equal to 3;

and fourthly, separating the LED wafer into a plurality of LED chips along the cutting channel.

The manufacturing method adopts a double-sided asymmetric multifocal invisible cutting mode, and aims at

Face close to slip face

Laser stealth dicing pairs using multiple foci

The crystal lattice direction of the optical fiber is subjected to vertical multi-point damage, so that cracks in the subsequent splitting process are prevented from being along a slip plane

The direction is cracked to obtain a substantially vertical LED chip with the side surfaces of the chip substrate making an angle of 90+/-5 degrees with the upper surface.

In some embodiments, the present invention provides a light emitting diode comprising a substrate and a light emitting epitaxial stack over an upper surface of the substrate, the light emitting epitaxial stack comprising, from a side of the substrate, a first type semiconductor layer, an active layer and a second type semiconductor layer, characterized in that: the substrate comprises a first side face and a second side face which are adjacent, the first side face is provided with X first cutting marks which are transversely arranged, the second surface is provided with Y second cutting marks which are transversely arranged, wherein Y is more than X and is more than or equal to 3.

The light-emitting diode is beneficial to forming a large modification part by adopting a laser beam with large pulse energy in the substrate through forming different numbers of cutting marks on different side surfaces, for example, forming a small number of cutting marks on the cutting surface of a non-easy-to-crack surface, and avoiding that light spots of the laser beam irradiate the epitaxial layer or the cutting marks extend to the light-emitting epitaxial structure, so that the epitaxial structure or the electrode is damaged to cause chip failure, and the needle is used for forming a large modification part on the substrate and preventing the laser beam from irradiating the epitaxial layer or the cutting marks from extending to the light-emitting epitaxial structureA greater number of cutting marks are formed on the cutting surface of the fracture surface, in one aspect

The LED chip is cracked in the direction to obtain a basically vertical side wall, and on the other hand, a fine concave-convex structure is formed on the side wall of the substrate, so that the side light-emitting efficiency of the LED chip is improved.

providing a laser beam to focus in the substrate, forming X cutting lines on the same section in the substrate along a first cutting direction, and forming Y cutting lines on the same section in the substrate along a second cutting direction, wherein the pulse energy of the laser beam in the first cutting direction is greater than that of the laser beam in the second cutting direction, Y is greater than or equal to X and greater than 0, and Y is greater than or equal to 3;

According to the manufacturing method of the light emitting diode, different laser energy is adopted in the cutting process to form cutting marks on different side faces respectively, for example, a laser beam with larger pulse energy is adopted for a cutting face located on a non-easy-to-crack face to form a larger modified part inside the substrate to ensure subsequent smooth splitting, and a laser beam with smaller pulse energy is adopted for a cutting face located on an easy-to-crack face to form a smaller modified part inside the substrate to prevent an epitaxial layer from being damaged in the laser etching process or prevent cracks in the splitting process from extending to the upper surface of the substrate to damage a semiconductor epitaxial laminated structure, an insulating layer or an electrode to cause chip failure.

In some embodiments, the present invention provides a light emitting diode comprising a substrate and a light emitting epitaxial stack on an upper surface of the substrate, the light emitting epitaxial stack comprising a first type semiconductor layer, an active layer and a second type semiconductor layer from a side of the substrate, characterized in that: the substrate comprises a first side face and a second side face which are adjacent, the first side face is provided with a first cutting mark, the included angle between the second side face and the upper surface of the substrate is 85-95 degrees, at least five second cutting marks which are transversely arranged are arranged, the distance between the two adjacent lines of the second cutting lines is larger than 0 and smaller than or equal to 30 micrometers, each second cutting mark comprises a series of explosion points which are positioned on the central line of the cutting line and cracks which are led out from each explosion point, and the cracks of the two adjacent cutting marks have a certain distance or are connected.

The substrate of the LED is of a crystal structure, the upper surface of the substrate is a C plane, the substrate is provided with a slip crack surface with the upper surface of the substrate at an included angle, and the second side surface is vertical to the C plane and is close to the slip crack surface

Therefore, at least five rows of second cutting marks arranged transversely are arranged on the second side surface, the distance between two adjacent lines of the second cutting lines is more than 0 and less than or equal to 30 mu m, and then the two lines of the second cutting marks are aligned

The direction is cracked to obtain substantially vertical sidewalls.

In some embodiments, the present invention provides a light emitting diode comprising a substrate and a light emitting epitaxial stack over a base upper surface, the light emitting epitaxial stack comprising, from a side of the substrate, a first type semiconductor layer, an active layer and a second type semiconductor layer, characterized in that: the substrate comprises a first side and a second side which are adjacent, the first side is provided with X first cutting marks, the second side is provided with Y second cutting marks, and the texture roughness of the first cutting marks is larger than that of the second cutting marks.

In the light emitting diode, thick and large cutting marks are formed on the difficult-to-crack surface, so that the cutting is facilitated on one hand, the light extraction efficiency is improved on the other hand, the thin cutting marks are formed on the easy-to-crack surface, the generation of large internal stress can be avoided, and further, the cracking caused in the cracking process is reduced, and the functional layers of the LED chip are damaged when the cracking reaches the first surface of the substrate.

In some embodiments, the present invention provides a light emitting diode comprising a substrate and a light emitting epitaxial stack over a base upper surface, the light emitting epitaxial stack comprising, from a side of the substrate, a first type semiconductor layer, an active layer and a second type semiconductor layer, characterized in that: the substrate is of a crystal structure and comprises a first side face and a second side face which are adjacent, wherein the second side face is a fracture face and comprises Y cutting marks which are arranged in parallel, and the size of the cutting texture of the first row close to one side of the luminous epitaxial lamination layer is smaller than the cutting marks of other rows.

By controlling the size of the cutting mark close to one side of the luminous epitaxial lamination to be smaller than the cutting mark below the luminous epitaxial lamination, the phenomenon that the cutting mark is subjected to external force in the splitting process, and the crack extends to the luminous epitaxial structure, so that the epitaxial structure is damaged can be well avoided.

In some embodiments, the present invention provides a light emitting diode comprising a substrate and a light emitting epitaxial stack over a base upper surface, the light emitting epitaxial stack comprising, from a side of the substrate, a first type semiconductor layer, an active layer and a second type semiconductor layer, characterized in that: the substrate is of a crystal structure and comprises a first side surface and a second side surface which are adjacent, wherein the first side surface is a non-breakable surface and at least comprises three first cutting marks which are transversely arranged, and the adjacent first cutting marks are not connected or connected but are not basically staggered with each other.

Additional features and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Drawings

The features and advantages of the present invention will be more clearly understood by reference to the accompanying drawings, which are illustrative and not to be construed as limiting the invention in any way.

Fig. 1 shows a lattice structure of a sapphire substrate.

Fig. 2 shows a real photograph of a conventional LED chip.

Fig. 3 is a photograph showing a real object in which the LED chips shown in fig. 2 are arranged on a substrate.

Fig. 4 shows a light distribution graph of the LED chip shown in fig. 2.

Fig. 5 shows a flow chart of a manufacturing process of an LED chip according to the present invention.

Fig. 6 to 9 are schematic structural diagrams of a manufacturing process flow of the LED chip shown in fig. 5. Wherein fig. 6 shows a side cross-sectional view of an LED epitaxial structure; FIG. 7 illustrates the definition of LED chip size and scribe lines in the epitaxial structure of FIG. 6, and FIG. 8 illustrates scribe lines formed inside the substrate in a first direction using a laser beam; fig. 9 illustrates a cutting line formed inside a substrate in a second direction using a laser beam; FIG. 10 illustrates a scribe line formed on a first side (corresponding to a first direction) of a substrate after cleaving; fig. 11 illustrates a scribe line formed on the second side (corresponding to the second direction) of the substrate after the breaking.

FIGS. 12-13 are SEM photographs showing LED chips formed by the LED manufacturing method of FIG. 5, wherein FIG. 12 shows a cut formed on a first side of the LED substrate, and FIG. 13 shows a cut formed on a second side of the LED substrate.

FIG. 14 illustrates a top view of an LED chip in accordance with the present invention.

Fig. 15 shows a flow chart of a process for fabricating an LED chip according to the present invention.

Fig. 16 and 17 are SEM photographs of the LED chip formed by the LED chip manufacturing method shown in fig. 15, in which fig. 16 shows a cut mark on the first side of the substrate of the LED chip, and fig. 17 shows a cut mark on the second side of the substrate of the LED chip.

Fig. 18 is a photograph showing a real photograph in which LED chips formed by the LED manufacturing method shown in fig. 15 are arranged on a substrate.

Fig. 19 shows a light distribution graph of the LED chip shown in fig. 18.

Fig. 20 illustrates another light emitting diode implemented in accordance with the present invention.

Fig. 21 shows another light emitting diode implemented in accordance with the present invention.

Fig. 22 illustrates another light emitting diode implemented in accordance with the present invention.

Fig. 23 shows an SEM photograph of the LED chip shown in fig. 22.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention.

Example one

The embodiment discloses a manufacturing method of an LED chip and the LED chip formed by the manufacturing method, which adopts lasers with different powers to perform multi-focus stealth cutting aiming at different crystal faces, wherein dense and small multi-point stealth cutting is utilized for the crystal face close to a slip face to form approximate continuous multi-point cutting so as to prevent crack edges in the splitting process

The face is cracked. Fig. 5 shows a flow of the manufacturing method, which mainly includes the following steps S110 to S140, which will be described in detail with reference to fig. 7 to 12. To be noted, this embodimentThe different powers of the laser light of the example refer to the power of a single focal spot.

Step S110: an LED wafer is provided that includes a substrate 110 and a light emitting epitaxial stack 120 thereon, as shown in fig. 6. Specifically, the substrate 110 is preferably a transparent or translucent material, and the light emitted from the light emitting epitaxial stack 120 can be emitted outward through the substrate 110, and is a growth substrate for growing the light emitting epitaxial stack 120, such as a sapphire substrate, a GaN substrate, an AlN substrate, and the like. The substrate 110 includes a first surface S11, a second surface S12, and a sidewall, wherein the first surface S11 is opposite to the second surface S22, and the substrate 110 may include a plurality of protrusions formed at least at a portion of the first surface S11. For example, the substrate 110 may be a patterned sapphire substrate. The light emitting epitaxial stack 120 may be epitaxially formed on the substrate 210 by Physical Vapor Deposition (PVD), Chemical Vapor Deposition (CVD), epitaxial Growth (epitaxial Growth Technology), Atomic Layer Deposition (ALD), etc., and generally includes the first conductive type semiconductor Layer 121, the active Layer 122, and the second conductive type semiconductor Layer 123, and a specific light emitting epitaxial stack 120 may include a iii-v type nitride-based semiconductor, for example, a nitride-based semiconductor such As (Al, Ga, In) N or a phosphide-based semiconductor including (Al, Ga, In) P or an arsenide-based semiconductor including (Al, Ga, In) As. The first conductive type semiconductor layer 121 may include n-type impurities (e.g., Si, Ge, Sn), and the second conductive type semiconductor layer 123 may include p-type impurities (e.g., Mg, Sr, Ba). Also, the above impurity types may be reversed. The active layer 122 may include a multiple quantum well structure (MQW) and the elemental composition ratio of the semiconductor may be adjusted to emit a desired wavelength.

Step S120: the surface of the LED wafer is defined with cutting channels, including a first cutting channel with a first cutting direction D1 and a second cutting channel with a second cutting direction D2, which are perpendicular to each other. Specifically, the substrate 110 has a crystal structure, wherein the first surface S11 of the substrate 100 is a C plane, the crystal structure includes a slip plane forming an angle with the C plane, and a crystal plane corresponding to the second direction D2 is perpendicular to the C plane and is close to the slip plane. In one embodiment, the substrate 110 is a sapphire material, wherein the first direction D1 corresponds to a non-breakable plane of a sapphire crystal, the second direction D2 corresponds to a breakable plane of the sapphire crystal, the LED wafer is divided into a series of light emitting cells by dicing streets, an electrode region is defined on each light emitting cell, the second conductive type semiconductor layer 123 and the active layer 122 in the electrode region are etched through one or more photomasks to expose a portion of the surface of the first conductive type semiconductor layer 121, and the second conductive type semiconductor layer 123, the active layer 122 and the first conductive type semiconductor layer 121 in the dicing street region are etched until the first surface S11 of the substrate 110.

An insulating layer 130 is further formed on the exposed surface and sidewalls of the light-emitting epitaxial stack 120. In the conventional coating process, such as evaporation or sputtering, the thickness of the insulating layer 130 on the sidewall of the light-emitting epitaxial stack is generally lower than the thicknesses on the top surface of the light-emitting epitaxial stack and the first surface of the substrate due to the shadow effect, so that the thickness on the sidewall of the light-emitting epitaxial stack is 40-90% of the thickness of the top surface of the semiconductor sequence. In one embodiment, the contact electrode 150 is formed on the surface of the second conductive type semiconductor layer 123, and the insulating layer 130 is formed after the material may be ITO, GTO, GZO, ZnO, or a combination of several materials. The first electrode 141 and the second electrode 142 are formed on the insulating layer by photolithography and evaporation processes. The minimum horizontal pitch of the first and

second electrodes

141 and 142 on the insulating layer 130 is preferably 5 μm or more, for example, 20 to 40 μm, or 40 to 60 μm, or 60 to 80 μm, and the material may be a combination of metals such as Cr, Pt, Au, Ti, Ni, and Al. Preferably, the electrode is a multilayer structure, and the surface layer of the electrode is preferably made of Au material. The first electrode 141 is electrically connected to the first conductive type semiconductor layer 121 through the opening structure 171 penetrating the insulating layer 130, and the second electrode 142 is electrically connected to the contact electrode 150 through the opening structure 172 penetrating the insulating layer 130.

Step S130: providing a laser beam focused inside the substrate 110, forming X cutting lines on the same cross section inside the substrate 110 along the first direction D1, and forming Y cutting lines (Y ≧ X ≧ Y) on the same cross section inside the substrate 110 along the second direction D21). Specifically, X first cutting lines are formed on the same cross section inside the substrate 110 by using a laser beam of a first pulse energy, as shown in fig. 8; the laser beam using the second pulse energy forms Y second cutting lines on the same cross section inside the substrate 110 in the second direction D2, as shown in fig. 9. In the present embodiment, the first direction D1 corresponds to a non-crack-prone surface, so a laser beam with a large power is used to form at least one continuous first cutting line 1110 inside the substrate 110, the distance between the first cutting line 1110 and the first surface of the substrate 110 is preferably 15 μm or more, so that the epitaxial layer is not damaged when the laser etching is performed on the inside of the substrate 110, for example, the distance may be 20 μm to 60 μm, and the distance between adjacent first cutting lines 1110 may be 10 μm to 50 μm. The first cutting line 1110 includes a series of first bursts 1111 arranged substantially at equal intervals and etched textures 1112 (modified regions) connected to the first bursts 1111, the etched textures 1112 being irregularly distributed textures. Preferably, the pitch of the adjacent first explosion points 1111 in the first row is preferably 1 μm or more and 12 μm or less, which affects the efficiency if less than 1 μm, and if more than 12 μm, the first cutting line 1110 may not be continuous and may cause difficulty in subsequent cleavage, which may be 3 to 5 μm, or 5 to 8 μm, or 8 to 12 μm, and in this embodiment, the pitch is preferably 3 to 7 μm. The second direction D2 corresponds to the easy-to-crack surface, so that a laser beam with a smaller power is used to form a plurality of discontinuous second cutting lines 1120 inside the substrate 110, the distance between the second cutting lines 1120 and the first surface S11 of the substrate 110 is preferably 10 μm or more, and more preferably 15-50 μm, the distance is too small, on one hand, the laser is easy to damage the epitaxial layer during the etching of the substrate, on the other hand, cracks generated during the splitting process may reach the epitaxial layer, the insulating layer or the electrode beyond the first surface S11 of the substrate 110, and if the distance is too large, the cracks are easy to follow during the splitting process

The lattice direction of (a) is subjected to oblique fracture. The cutting line 1120 is composed of a series of spaced apart textures, and is arranged regularly relative to the first, and the cutting line 112 includes a series of second shots and textures extending outward from the second shots, adjacent first shotsThe distance between two explosion points is preferably 5 μm or more and 20 μm or less, and in one embodiment the distance is 8 to 12 μm.

In the present embodiment, a single-blade multi-focus laser beam is preferably used in the first direction D1 and the second direction D2, wherein the average power of the single focus of the first laser beam may be 0.07-5 mw, and the average power of the single focus of the second laser beam may be 0.03-3 mw.

Step S140: and separating the LED wafer into a plurality of LED chips along the cutting channel. Referring to fig. 10 and 11, the first side surface (corresponding to the first cutting direction) of the LED chip is formed with at least two parallel rows of first cut lines 111, the first cut lines 111 including cracks 1113 extending upward and downward from the first cut lines 1110; the second side of the LED chip (corresponding to the second cutting direction) has at least two parallel second cuts 112 and a transverse crack 113, the texture of the second cuts 112 being relatively regular and thinner than the texture of the first cuts 111. Fig. 12 shows an SEM photograph of a first side of an LED chip formed according to the manufacturing method of the present embodiment, the first side including two parallel first cut marks 111. As can be seen from the figure, the first scribe lines 111 include first scribe lines 1110 and cracks 1113 extending upward and downward from the first scribe lines 1110, wherein the first scribe line is close to the upper surface of the substrate 110, a distance H11 between the first explosion point 1111 and the upper surface S11 of the substrate is 30-60 μm, such as 40 μm, the second scribe line 111 is close to the second surface S12 of the substrate 110, and a distance H12 between the first explosion point 1111 and the second surface S12 of the substrate 110 is 20-50 μm, such as 30 μm or 50 μm. In the present embodiment, the distance between the first detonation 1111 and the first surface S11 of the substrate 110 is controlled so that the first crack 1113 does not reach the first surface S11 of the substrate as much as possible. Fig. 13 shows an SEM photograph of the second side of the LED chip formed according to the manufacturing method of the present embodiment, which includes a plurality of parallel second cuts 112. As can be seen from the figure, the second scribe 112 includes a crack 1122 located on and extending from the second scribe 1120 in the up and down direction, wherein a first second scribe 112 is close to the first surface S11 of the substrate 110, and a distance H21 between a second explosion point and the first surface S11 of the substrate 110 is 20-60 μm, a second scribe is close to the second surface S12 of the substrate 110, and a distance H22 between the explosion point and the second surface S12 of the substrate 110 is 10-60 μm, for example, 30 μm-50 μm, wherein the crack of the first scribe does not reach the first surface S11 of the substrate 110 and has a size smaller than that of the crack of the second scribe, and the crack of the second scribe extends toward the second surface S12 of the substrate 110 and partially reaches or approaches the second surface S12 of the substrate 110. Further, a cross grain 113 is further included below the first cut, and the crack 1122 of the first cut extends toward the second surface S12 of the substrate 110 and terminates at the cross grain 113.

In this embodiment, different laser energies are used to form cutting marks on different side surfaces during the cutting process, for example, a laser beam with a larger pulse energy is used for a cutting surface located on a non-cleavage-prone surface to form a larger modified portion inside the substrate 110, so as to ensure that subsequent smooth cleaving is performed, thereby avoiding a twinning problem (i.e., two chips are not separated) that often occurs during cutting, and a laser beam with a smaller pulse energy is used for a cutting surface located on a cleavage-prone surface to form a smaller modified portion inside the substrate 110, thereby avoiding a crack extending onto the first surface S11 of the substrate 110 during the subsequent cleaving process from damaging the structure of the semiconductor epitaxial stack 120 or causing a chip failure due to an electrode.

Fig. 14 shows a top view of an LED chip, specifically a rectangular or square flip-chip LED chip, implemented in accordance with the present invention. The LED chip comprises the following stacked layers: a substrate 110, a light emitting epitaxial stack 120, an insulating layer 130, a first electrode 141, and a second electrode 142. The substrate 110 includes four sides a 1-a 4 surrounding clockwise, wherein the sides a1 and A3 are parallel and short sides, and the sides a2 and a4 are parallel and long sides. The LED chip may be a small-sized LED chip having a small horizontal area, for example, may have a size of about 62500 μm²The horizontal cross-sectional area of which is about 900 μm²Above and about 62500 μm²The size of the LED chip can pass through the substrate 11The size of the first surface S11 of 0 reflects, for example, that the side length of the first surface S11 of the transparent substrate 110 is preferably 300 μm or less, preferably 200-300 μm, or 100-200 μm, or smaller than 100 μm, preferably 30-150 μm. The thickness of the substrate 110 is preferably between 30 μm and 160 μm, such as 50 μm to 80 μm, or 80 μm to 120 μm, or 120 μm to 160 μm. The thickness of the light-emitting epitaxial stack 120 is between 4 μm and 10 μm. The LED chip of the present embodiment has the above-described size and thickness, and thus the LED chip can be easily applied to various electronic devices requiring a small and/or thin light emitting device.

Fig. 12 schematically shows a side of a substrate 110 of an LED chip according to the present invention corresponding to the side a1 or A3, the substrate side including two parallel first cuts 111, and fig. 13 schematically shows a side of the substrate 110 corresponding to the side a2 or a4, the substrate including two parallel second cuts 112 and a transverse crack 113 located under the first second cut 112. As can be seen from the figure, the size and roughness of the first cut 111 are larger than those of the second cut 112. In the embodiment, for the hard cracking surfaces of the edges a1 and A3, a modified portion with a larger size is formed inside the substrate 110 to ensure subsequent smooth cracking and avoid the twinning problem (i.e., the two chips are not separated) during dicing, and for the easy cracking surfaces of the edges a2 and a4, a smaller modified portion is formed inside the substrate 110 to avoid the crack extending to the first surface of the substrate 110 during the subsequent cracking process to damage the semiconductor epitaxial stacked structure or the electrode and cause the chip failure.

Further, the insulating layer 130 is an insulating reflective layer covering the top surface and the sidewalls of the light emitting epitaxial stack, and when the light radiated by the light emitting layer reaches the surface of the insulating layer 130 through the contact electrode 150, most of the light may be reflected by the insulating layer 130 to return to the light emitting epitaxial stack 120, and most of the light exits through the second surface S11 side of the substrate 110, reducing light loss caused by light exiting from the surface and the sidewalls of the light emitting epitaxial stack 120. Preferably, the insulating layer 130 is capable of reaching at least 80% or further at least 90% of its surface for the light radiated by said luminescent layerA proportional amount of light intensity is reflected. The insulating layer 130 may specifically include a bragg reflector. The bragg reflector may be formed in such a manner that at least two insulating media having different refractive indexes are repeatedly stacked, and may be formed in 4 to 20 pairs, for example, the insulating layer may include TiO₂、SiO₂、HfO₂、ZrO₂、Nb₂O₅、MgF₂And the like. In some embodiments, the insulating layer 130 may be deposited with TiO alternately₂layer/SiO₂And (3) a layer. Each layer of the bragg reflector may have an optical thickness of 1/4 a peak wavelength of a radiation band of the light emitting layer. The uppermost layer of the bragg reflector may be formed of SiNx. The layer formed of SiNx is excellent in moisture resistance, and can protect the light emitting diode from moisture. In the case where the insulating layer 230 includes a bragg reflector, the lowermost layer of the insulating layer 130 may have a bottom layer or an interface layer that improves the film quality of the distributed bragg reflector. For example, the insulating layer 130 may include SiO with a thickness of about 0.2 to 1.0 μm₂Forming an interface layer and stacking a TiO layer on the interface layer at a specific period₂/SiO₂。

In some embodiments, the insulating layer 130 may be a single insulating layer, preferably having a reflectivity generally lower than that of the Bragg reflector, and at least 40% of the light is emitted from the insulating layer 130, preferably at least 1 μm or more preferably a thickness of 2 μm or more, such as SiO₂The LED has excellent moisture resistance and can protect the LED from moisture.

The contact electrode 150 may be in ohmic contact with the second conductive type semiconductor layer 123. The contact electrode 150 may include a transparent conductive layer. The transparent conductive layer may further include at least one of a light-transmitting conductive oxide such as indium tin oxide, zinc indium tin oxide, indium zinc oxide, zinc tin oxide, gallium indium tin oxide, indium gallium oxide, zinc gallium oxide, aluminum-doped zinc oxide, fluorine-doped tin oxide, or the like, and a light-transmitting metal layer such as Ni/Au, or the like, for example. The conductive oxide may also include various dopants. Preferably, the thickness of the contact electrode 150 is 20 to 300 nm. The surface contact resistance of the contact electrode 150 with the second conductive type semiconductor layer 123 is preferably lower than the surface contact resistance of the metal electrode with the second conductive type semiconductor layer 123, and thus the forward voltage can be reduced and the light emitting efficiency can be improved.

The first electrode 141 and the second electrode 142 are of a multilayer structure, and the bottom layer is one or a combination of multiple stacked layers of metal materials of Cr, Al, Ti, Ni, Pt and Au. In some embodiments, the surface layers of the first and second electrodes are Sn-containing metal materials, and in other embodiments, the surface layers of the first and second electrodes may also be Au metal materials.

Example two

Fig. 15 shows another method for manufacturing an LED chip according to the present invention, which mainly includes the following four steps: step S210: providing an LED wafer comprising a substrate 110 and a light emitting epitaxial stack 120 on a first surface S11 of the substrate 110;

step S220: defining a cutting channel on the surface of the LED wafer, wherein the cutting channel comprises a first cutting direction D1 and a second cutting direction D2 which are perpendicular to each other;

step S230: providing a laser beam to focus inside the substrate 110, forming X cutting lines on the same cross section inside the substrate along a first direction, and forming Y cutting lines on the same cross section inside the substrate along a second direction, wherein Y is greater than X >0, and Y is greater than or equal to 3;

step S240: and separating the LED wafer into a plurality of LED chips along the cutting channel.

Steps S210, S220 and S240 can be performed with reference to steps S110, S120 and S140 of the first embodiment, and the following description focuses on step S230.

In the present embodiment, the cutting surface close to the slip surface is aimed at

Performing multifocal stealth dicing with a low-power laser, the number of stealth dicing points being preferably 3 or more and 20 or less, performing dense and small multipoint stealth dicing to form nearly continuous multipoint dicing in the thickness direction of the same dicing surface, and performing multifocal stealth dicing on the same dicing surface

The crystal lattice direction of the surface is subjected to vertical multipoint destruction, so that cracks in the subsequent splitting process can be extended

The direction cracks, and the verticality of the LED chip reaches 90+/-5 degrees.

Specifically, first, a laser beam is focused inside the substrate 110, X cutting lines are formed on the same cross section inside the substrate in the first direction D1, and Y cutting lines are formed on the same cross section inside the substrate 110 in the second direction D2. In the embodiment, the first direction D1 corresponds to a hard-crack surface, so a laser beam with a larger power is used to form 1 to 10 cutting lines, preferably 2 to 5 cutting lines, when one cutting line (i.e. single-focus cutting) is formed, a laser beam with a larger power needs to be used for etching, a formed cutting trace may be difficult to control, on one hand, the probability of a twin-crystal problem (i.e. no separation between two chips) during cutting is increased, and on the other hand, a crack may reach the first surface S11 of the substrate 110 during the cracking process, and further damage the semiconductor light emitting stack 120, the insulating layer or the electrode, resulting in failure of the LED chip. The distance between the center line (i.e., the focal point) of the first cutting line 111 and the first surface S11 of the substrate 110 is preferably 10 μm or more, more preferably 15 μm or more, and may be 20 μm or 30 μm or 35 μm or 50 μm, for example, when the distance is less than 10 μm, cracks generated during texture or splitting by laser etching may easily reach above the first surface S11 of the substrate 110, thereby damaging the semiconductor light emitting stack 120, the insulating layer, or the electrode, and causing the LED chip to fail. The second direction D1 corresponds to the easy-to-crack surface, so that 3 to 20 cutting lines, preferably 5 to 16 cutting lines are formed by using a laser beam with a smaller power, so that the effect of vertical cutting can be achieved, and the appearance of the chip viewed from the top view direction shown in fig. 18 is in a square wave-free shape. The distance between the center line (i.e., focal point) of the second scribe line 112 and the upper surface S11 of the substrate is preferably 5 μm or more, more preferably 15 μm or more, and may be 16 μm, 20 μm, 30 μm, or 35 μm, for example, and when the distance is less than 5 μm, cracks generated during the laser etching of the texture or the splitting process are easily reachedWhen the distance exceeds 50 μm, cracks are easily formed during the splitting process, which is above the first surface S11 of the substrate 110 to damage the semiconductor light emitting stack, the insulating layer, or the electrodes, thereby causing the LED chip to fail

Oblique cracking occurs. Preferably, the Y second cutting lines are formed by a single blade with multiple focuses, so that on one hand, a double-line split appearance can be avoided, and on the other hand, the efficiency of laser cutting can be improved.

In one embodiment, the substrate 110 has a thickness of 120 μm to 150 μm, two first scribe lines 111 are formed on the same scribe plane in the first direction D1, a position of a center line (i.e., a focal point) of the first scribe line closest to the first surface S11 of the substrate 111 is 35 μm to 50 μm from the first surface S11 of the substrate 110, 7 to 9 second scribe lines 112 are formed on the same scribe plane in the second direction D2, and a position of a center line (i.e., a focal point) of the second scribe line 112 closest to the first surface S11 of the substrate 10 is 20 μm to 35 μm from the first surface S11 of the substrate 10, and SEM photographs of two sides of the substrate 110 are shown in fig. 16 and 17, respectively, wherein the first side has two first scribe lines 111 and the second side has seven second scribe lines 112 and 6 transverse cracks 113. As can be seen from the figure, the single first cut 111 is thicker than the second cut 112, specifically has a wider dimension in the thickness direction of the substrate and a greater depth in the direction perpendicular to the thickness direction of the substrate 110, and the shape of the first cut 111 is in a zigzag shape with irregular upper and lower parts, the second cut 112 is composed of a series of equally spaced textures, and a transverse crack 113 is formed between two adjacent second cuts 112.

The structure layer of the LED chip formed by the LED chip manufacturing method of this embodiment is substantially the same as the structure layer of the LED chip of the first embodiment, and details are not repeated here. The difference is mainly in the topography of the substrate 110: (1) the second side (long side) of the substrate 110 is substantially perpendicular to the first surface S11 of the substrate 110 within 90+/-5 ° of the angle α, as shown in fig. 16; (2) the shapes of the LED chips are more regular, and fig. 18 shows a photograph of a real object in which the LED chips formed by the LED manufacturing method of the present embodiment are arranged on the substrate, which shows that each LED chip is rectangular and the edge of each LED chip is not significantly distorted; (3) the second side surface of the LED chip substrate 110 except the upper and lower regions is a flat region, the middle region is a roughened region occupied by the second cutting trace 112 and the transverse crack 113, the adjacent second cutting trace 112 substantially reaches the transverse crack located therebetween to form a substantially continuous longitudinal cutting line 114 (thickness direction), wherein the area of the roughened region occupies more than 60% of the area of the side surface, preferably 60% to 80%, so that the risk of electrical leakage (laser cutting or crack damage each functional layer of the LED) can be reduced, and on the other hand, the substrate 110 has light transmittance and a larger thickness, which is more beneficial to light extraction from the side surface of the light emitted by the active layer of the LED chip and increases the light extraction efficiency. Fig. 19 shows a light distribution graph of the LED chip shown in fig. 18, and it can be seen that the light pattern is symmetrical.

In the embodiment, different numbers of cutting marks are formed on different side surfaces of the substrate 110, a small number of cutting marks (for example, 2 to 5 cutting marks) are formed on the cutting surfaces located on the non-breakable surfaces, which is beneficial to forming a large modified part inside the substrate by using a laser beam with large pulse energy, and preventing the cutting marks from extending to the light-emitting epitaxial structure, thereby damaging the epitaxial structure or causing chip failure, a large number of cutting marks (for example, 5 to 20 cutting marks) are formed on the cutting surfaces located on the m-plane and other breakable surfaces, a longitudinal cutting line similar to continuity is formed in the thickness direction of the substrate 110, and further, the substrate 110 is subjected to surface treatment

The direction is cracked to obtain substantially vertical sidewalls. The advantageous effects of the present embodiment will be described below with reference to comparative examples.

(I) testing of light efficiency

Sample a and sample B (comparative example) were prepared and the light output efficiency thereof was measured, wherein sample a was prepared by the method described in this embodiment, it should be noted that sample a and sample B were prepared by using LED wafers with the same structure, and the processes and conditions of steps S210, S220 and S240 were the same, sample a was specifically prepared in step S230 by using a bifocal laser beam to form 2 first cutting lines on the same cross section inside the D1 substrate 110 along the first direction, using a multifocal laser beam to form 7 first cutting lines on the same cross section inside the substrate 110 along the second direction D2, and performing splitting to form LED chips, and the specific structure thereof is described with reference to fig. 16 and 17. Sample B was subjected to the single focus dicing of the same section inside the substrate 110 in the first and second directions D1 and D2, respectively, and then to the splitting to form LED chips, as shown in fig. 2, in step S230. The light output efficiency was measured for 10 chips each, and the results are referred to in table one. As can be seen from the table one, the LED chip of the present embodiment has an earlier light emitting efficiency, which is improved by about 3%.

Table one:

(II) leakage test

The LED wafer with the same epitaxial structure is adopted to respectively manufacture samples B, C and D, the laser focal points of the three samples for invisible cutting are different, and the rest are the same, specifically as follows: the sample B is cut in the inner part of the substrate by adopting single focus focusing on both the easy cracking surface (D2 direction) and the non-easy cracking surface (D1 direction); the sample C adopts a 9-focus laser beam on the surface easy to crack and adopts a 2-focus laser beam on the surface not easy to crack for laser cutting; and the sample D adopts 9-focus laser beams to carry out laser cutting on both the easy-to-crack surface (D2 direction) and the non-easy-to-crack surface (D1 direction), and a leakage current test is carried out after splitting, and when the IR is greater than 0.1 muA, the sample D is judged to be the leakage current, and the test results are shown in the table II. See table two: the number of the leakage current chips of the single LED wafer split of the sample B is the largest, and one of the main reasons is that the cracks generated during the splitting process by the single focus cutting are difficult to control and easily damage each functional layer of the LED chip, and the average number of the leakage current chips of the single LED wafer split of the sample D and the sample C is the smallest.

Table two:

EXAMPLE III

Fig. 20 shows a schematic diagram of an LED chip according to the present invention. The LED chip is also a flip-chip type LED chip, and light emitted from the active layer 122 is emitted from the substrate 110. The differences from the LED chip shown in the first embodiment are mainly as follows: the LED chip is provided with a reflective layer 160 on the second surface S12 of the substrate 110. The reflective layer 160 may be a single layer or a multi-layer structure, so that the light emitting angle of the LED chip may be increased to 160 ° or more. The reflective layer 160 covers at least the middle region of the second surface S12 of the substrate 110, and may also completely cover the second surface of the substrate. Preferably, the reflective layer 160 is an insulating reflective layer, and can be formed by alternately stacking high and low refractive index materials, such as SiO₂And TiO₂Alternately stacked.

The LED chip described in this embodiment may be suitable for a backlight module of a display device, and the reflective layer 160 is disposed on the second surface S12 of the LED chip substrate 10, so as to change the light emitting path of the LED chip and further increase the light emitting angle of the LED chip, which is beneficial to reducing the thickness of the backlight module and reducing the size of the backlight module.

Example four

Fig. 21 shows a schematic diagram of an LED chip implemented according to the present invention. The light emitting epitaxial stack 120 of the LED chip shown in the previous embodiments is formed on the substrate 110 by epitaxial growth, and in the present embodiment, the light emitting epitaxial stack 120 is formed on the substrate 110 by the bonding layer 180. In one embodiment, the light emitting epitaxial stack 120 is an AlGaInP-based semiconductor layer, the AlGaInP-based epitaxial structure is grown on a gaas substrate, and then transferred to the transparent substrate 110 by means of transfer.

EXAMPLE five

Fig. 22 shows a schematic diagram of an LED chip according to the present invention. Different from the LED chip shown in the first embodiment: at least three rows of cuts are formed in the difficult-to-crack surface of the substrate by using a relatively low power laser beam, and the series of cuts may be unconnected or connected but not substantially staggered. The scribe lines 111A close to the first and second surfaces S11 and S12 of the substrate 110 are saw-toothed, and have a series of explosion points 111A-1 and cracks 111A-2 extending from the explosion points to the first surface S11 and the second surface S12, and the scribe lines 111-B in the middle area are formed by a series of laser etching.

Fig. 23 shows an SEM photograph of the side surface, and a fine and dense uneven structure is formed on the non-cleavage-prone surface formed in this way, and the area ratio of the uneven structure on the side surface can reach more than 50%, which is beneficial to cutting the chip and reducing the risk of damaging each functional layer of the chip, and is beneficial to increasing the light extraction efficiency of the LED chip from the side surface of the substrate.

EXAMPLE six

The embodiment discloses a deep ultraviolet LED chip, wherein the thickness of the substrate 110 is 200 μm to 750 μm, so that the surface easy to crack needs to be cut by multiple knives and multiple focuses. In one embodiment, the substrate 110 of the LED chip has a thickness of 350 to 500 μm, and the substrate is cut by a laser beam with a single 9-focus in a first direction D1 (non-cleavage-prone surface) and a laser beam with a 3-knife 9-focus in a second direction D2 (cleavage-prone surface). In another embodiment, the substrate has a thickness in excess of 500 μm, and therefore is cut in a first direction (non-fracture surface) with a 9-focal laser beam that can be applied with 3 knives and in a second direction (fracture surface) with a 9-focal laser beam that can be applied with 5 knives.

The foregoing embodiments are merely illustrative of the principles of this invention and its efficacy, rather than limiting it, and various modifications and variations can be made by those skilled in the art without departing from the spirit and scope of the invention, which is defined in the appended claims.

Claims

1. The manufacturing method of the light-emitting diode comprises the following steps:

secondly, defining a cutting channel on the upper surface of the LED wafer, wherein the cutting channel comprises a first cutting direction and a second cutting direction which are vertical to each other;

2. The method of claim 1, wherein: the substrate is a sapphire substrate, the first direction corresponds to a non-cracking surface of the sapphire crystal, and the second direction corresponds to a cracking surface of the sapphire crystal.

3. The method of claim 1, wherein: and forming the X cutting lines on the same cross section in the substrate along a first direction by using a first laser beam, and forming the Y cutting lines on the same cross section in the substrate along a second direction by using a second laser beam, wherein the pulse energy of the first laser beam is greater than that of the second laser beam.

4. The method of claim 1, wherein: wherein x is more than or equal to 1 and less than or equal to 5.

5. The method of claim 1, wherein: wherein y is more than or equal to 3 and less than or equal to 20.

6. The method of claim 1, wherein: wherein x is more than or equal to 1 and less than or equal to 3, and y is more than or equal to 5 and less than or equal to 20.

7. The method of claim 1, wherein: and forming a cutting line in the substrate by adopting a single-blade multi-focus mode.

8. The method of claim 1, wherein: the thickness of the substrate is greater than or equal to 80 μm and less than or equal to 200 μm, or greater than 200 μm and less than 750 μm.

9. The method of claim 1, wherein: the distance between the focusing point of the laser beam in the substrate and the upper surface of the substrate is greater than or equal to 10 μm.

10. The light emitting diode comprises a substrate and a light emitting epitaxial lamination layer positioned on the upper surface of the substrate, wherein the light emitting epitaxial lamination layer comprises a first type semiconductor layer, an active layer and a second type semiconductor layer from one side of the substrate, and the light emitting epitaxial lamination layer is characterized in that: the substrate comprises a first side face and a second side face which are adjacent, the first side face is provided with X first cutting marks which are transversely arranged, the second surface is provided with Y second cutting marks which are transversely arranged, wherein Y is more than X and is more than or equal to 3.

11. The led of claim 10, wherein: the included angle between the first side surface and the upper surface of the substrate and the included angle between the second side surface and the upper surface of the substrate are 85-95 degrees.

12. The led of claim 10, wherein: the X first cutting marks which are transversely arranged are connected or staggered with each other, and the Y second cutting marks are arranged in order.

13. The led of claim 10, wherein: the texture of the X first cutting marks arranged transversely is thicker than that of the Y second cutting marks.

14. The led of claim 10, wherein: at least one cutting mark in the X first cutting marks arranged transversely comprises a first explosion point positioned on the central line of the cutting mark and a texture extending outwards irregularly from the first explosion point.

15. The led of claim 10, wherein: at least one cutting mark of the Y first cutting marks arranged transversely comprises a second explosion point positioned on the central line of the cutting mark and a crack led out from the second explosion point, and the cracks of two adjacent cutting marks have a certain distance or are connected.

16. The led of claim 10, wherein: the at least three transversely arranged first cutting marks are included, and adjacent first cutting marks are not connected or connected but are not basically staggered with each other.

17. The light-emitting diode of claim 16, wherein the light-emitting diode is larger than: the first cutting marks near the upper and lower surfaces of the substrate are saw-toothed and have a series of explosion points and cracks from the explosion points to the upper and lower surfaces, and the first cutting mark in the middle area is formed by a series of laser etching.

18. The led of claim 10, wherein: the Y second cutting marks which are transversely arranged are arranged in parallel, and the distance between two adjacent second cutting lines is more than 0 and less than or equal to 30 mu m.

19. The led of claim 10, wherein: the area of the second cut mark on the second side surface is 50% or more.

20. The led of claim 10, wherein: the thickness of the substrate is 80-200 μm, the first side surface has 2-5 first cutting marks, and the second side surface has 5-20 cutting marks.

21. The led of claim 10, wherein: the distance between the central line of the first cutting mark and the upper surface of the substrate is more than 15 μm, and the distance between the central line of the second cutting mark and the upper surface of the substrate is more than 10 μm.

22. The led of claim 10, wherein: the second side surface further includes a transverse crack which is substantially parallel to the upper surface of the substrate, and the second cut is extended upward and downward in the thickness direction of the substrate and is stopped at the transverse crack.

23. The led of claim 10, wherein: the upper surface of the substrate has a regular shape.

24. The led of claim 10, wherein: the upper surface of the substrate is rectangular and comprises a first side length and a second side length, wherein the first side length is a short side and corresponds to the first side surface of the substrate, and the second side length corresponds to the second side surface of the substrate.

25. The led of claim 10, wherein: the side length of at least one edge of the upper surface of the transparent substrate is between 200 and 300 μm, or between 100 and 200 μm, or between 40 and 100 μm.

26. The led of claim 10, wherein: the light emitting epitaxial stack is formed on the substrate by epitaxial growth.

27. The led of claim 10, wherein: the light emitting epitaxial stack is bonded to the substrate by a transparent bonding layer.

28. The led of claim 10, wherein: the light-emitting epitaxial layer further comprises a first insulating reflecting layer which is formed on the light-emitting epitaxial laminated layer.

29. The led of claim 10, wherein: the display device further comprises a second reflecting layer which is formed on the lower surface of the substrate.

30. The light emitting diode comprises a substrate and a light emitting epitaxial lamination layer positioned on the upper surface of the substrate, wherein the light emitting epitaxial lamination layer comprises a first type semiconductor layer, an active layer and a second type semiconductor layer from one side of the substrate, and the light emitting epitaxial lamination layer is characterized in that: the substrate comprises a first side face and a second side face which are adjacent, the first side face is provided with a first cutting mark, the included angle between the second side face and the upper surface of the substrate is 85-95 degrees, at least five second cutting marks which are transversely arranged are arranged, the distance between the two adjacent lines of the second cutting lines is larger than 0 and smaller than or equal to 30 micrometers, each second cutting mark comprises a series of explosion points which are positioned on the central line of the cutting line and cracks which are led out from each explosion point, and the cracks of the two adjacent cutting marks have a certain distance or are connected.

31. Light emitting diode, including the base plate and lie in the epitaxial lamination of luminous on the base upper surface, this luminous epitaxial lamination includes first type semiconductor layer, active layer and second type semiconductor layer from base plate one side, its characterized in that: the substrate comprises a first side and a second side which are adjacent, the first side is provided with X first cutting marks, the second side is provided with Y second cutting marks, and the texture roughness of the first cutting marks is larger than that of the second cutting marks.

32. The led of claim 31, wherein: the second side further includes a transverse crack substantially parallel to the upper surface of the substrate.

33. The led of claim 31, wherein: the first cutting mark comprises a series of first explosion points and first etching textures extending outwards from the first explosion points, the second cutting mark comprises a series of second explosion points and second etching textures extending outwards from the second explosion points, and the distance between the first explosion points is smaller than that between the second explosion points.

34. The led of claim 33, wherein: the pitch of the first explosion points is more than or equal to 1 mu m and less than or equal to 12 mu m, and the pitch of the second explosion points is more than or equal to 5 mu m and less than or equal to 20 mu m.

35. The led of claim 33, wherein: adjacent first etched textures intersect and adjacent second etched textures do not intersect.

36. Light emitting diode, including the base plate and lie in the epitaxial lamination of luminous on the base upper surface, this luminous epitaxial lamination includes first type semiconductor layer, active layer and second type semiconductor layer from base plate one side, its characterized in that: the substrate is of a crystal structure and comprises a first side surface and a second side surface which are adjacent, wherein the first side surface is a non-breakable surface and at least comprises three first cutting marks which are transversely arranged, and the adjacent first cutting marks are not connected or connected but are not basically staggered with each other.

37. A light emitting diode according to the moat of claim 36, characterized by: the first cutting marks near the upper and lower surfaces of the substrate are saw-toothed and have a series of explosion points and cracks from the explosion points to the upper and lower surfaces, and the first cutting mark in the middle area is formed by a series of laser etching.

38. The manufacturing method of the light-emitting diode comprises the following steps: